1 Samuel 16: 4-13 (NRSV)
4Samuel did what the Lord commanded, and came to Bethlehem. The elders of the city came to meet him trembling, and said, “Do you come peaceably?” 5He said, “Peaceably; I have come to sacrifice to the Lord; sanctify yourselves and come with me to the sacrifice.” And he sanctified Jesse and his sons and invited them to the sacrifice.
6When they came, he looked on Eliab and thought, “Surely the Lord's anointed is now before the Lord.” 7But the Lord said to Samuel, “Do not look on his appearance or on the height of his stature, because I have rejected him; for the Lord does not see as mortals see; they look on the outward appearance, but the Lord looks on the heart.” 8Then Jesse called Abinadab, and made him pass before Samuel. He said, “Neither has the Lord chosen this one.” 9Then Jesse made Shammah pass by. And he said, “Neither has the Lord chosen this one.” 10Jesse made seven of his sons pass before Samuel, and Samuel said to Jesse, “The Lord has not chosen any of these.” 11Samuel said to Jesse, “Are all your sons here?” And he said, “There remains yet the youngest, but he is keeping the sheep.” And Samuel said to Jesse, “Send and bring him; for we will not sit down until he comes here.” 12He sent and brought him in. Now he was ruddy, and had beautiful eyes, and was handsome. The Lord said, “Rise and anoint him; for this is the one.” 13Then Samuel took the horn of oil, and anointed him in the presence of his brothers; and the spirit of the Lord came mightily upon David from that day forward. Samuel then set out and went to Ramah.